This is the top-level container element for every wxi file.

• AppId (min: 0, max: unbounded)
• Binary (min: 0, max: unbounded)
• Category (min: 0, max: unbounded)
• Certificate (min: 0, max: unbounded)
• Class (min: 0, max: unbounded)
• ComplianceCheck (min: 0, max: unbounded)
• Condition (min: 0, max: unbounded)
• CopyFile (min: 0, max: unbounded)
• CreateFolder (min: 0, max: unbounded)
• CustomAction (min: 0, max: unbounded)
• CustomActionRef (min: 0, max: unbounded)
• CustomTable (min: 0, max: unbounded)
• Directory (min: 0, max: unbounded)
• DirectoryRef (min: 0, max: unbounded)
• EnsureTable (min: 0, max: unbounded)
• Environment (min: 0, max: unbounded)
• Extension (min: 0, max: unbounded)
• Feature (min: 0, max: unbounded)
• FeatureRef (min: 0, max: unbounded)
• File (min: 0, max: unbounded)
• FileShare (min: 0, max: unbounded)
• FragmentRef (min: 0, max: unbounded)
• Group (min: 0, max: unbounded)
• Icon (min: 0, max: unbounded)
• IniFile (min: 0, max: unbounded)
• Interface (min: 0, max: unbounded)
• IsolateComponent (min: 0, max: unbounded)
• Media (min: 0, max: unbounded)
• ODBCDataSource (min: 0, max: unbounded)
• ODBCDriver (min: 0, max: unbounded)
• ODBCTranslator (min: 0, max: unbounded)
• ProgId (min: 0, max: unbounded)
• Property (min: 0, max: unbounded)
• PropertyRef (min: 0, max: unbounded)
• Registry (min: 0, max: unbounded)
• RemoveFile (min: 0, max: unbounded)
• RemoveFolder (min: 0, max: unbounded)
• ReserveCost (min: 0, max: unbounded)
• ServiceConfig (min: 0, max: unbounded)
• ServiceControl (min: 0, max: unbounded)
• ServiceInstall (min: 0, max: unbounded)
• SFPCatalog (min: 0, max: unbounded)
• Shortcut (min: 0, max: unbounded)
• SqlDatabase (min: 0, max: unbounded)
• SqlScript (min: 0, max: unbounded)
• SqlString (min: 0, max: unbounded)
• TypeLib (min: 0, max: unbounded)
• UI (min: 0, max: unbounded)
• UIRef (min: 0, max: unbounded)
• Upgrade (min: 0, max: unbounded)
• User (min: 0, max: unbounded)
• WebApplication (min: 0, max: unbounded)
• WebAppPool (min: 0, max: unbounded)
• WebDir (min: 0, max: unbounded)
• WebDirProperties (min: 0, max: unbounded)
• WebFilter (min: 0, max: unbounded)
• WebLog (min: 0, max: unbounded)
• WebProperty (min: 0, max: unbounded)
• WebServiceExtension (min: 0, max: unbounded)
• WebSite (min: 0, max: unbounded)
• WebVirtualDir (min: 0, max: unbounded)
• Sequence (min: 1, max: 1)
  1. InstallExecuteSequence (min: 0, max: 1)
  2. InstallUISequence (min: 0, max: 1)
  3. AdminExecuteSequence (min: 0, max: 1)
  4. AdminUISequence (min: 0, max: 1)
  5. AdvertiseExecuteSequence (min: 0, max: 1)